Conclusion

Secondly why use radare2 for analysis and Capstone API for scripting when you can use radare2 for both tasks without any effort.

The APIs, though different, produce the same results as expected. Radare2 will have the advantage though, as additional functionalities such as analysis (cross-references) and debugging for example can be applied to the data coming from Capstone. Additionally, radare2 also provides an embedded disassembler.

It makes more sense to compare radare2’s ESIL engine to the Unicorn Engine, or Udis to Capstone.